A customer has two single cluster IBM TS7700 Virtualization Engines at the same site. The customer wants to move one to a remote site and set up a grid configuration with the two clusters. The customer has fibre between the two sites. What is the most important factor to consider when planning the new configuration?（）

A. operator training
B. cache size of the two clusters
C. fibre bandwidth capability between the sites
D. number of stacked tape drives attached to each cluster